mem ,The Sw i tried using didnt work for me :-( ( I sent you PM with the problem)But I manged to get the uFAT runing and reading from my SD!!!coolBut write doesn't work .. tried two SDs - they are not write protected .. but I cant write to them (only read the stuff I wrote in the file on windows) :-(any help ? (no errors...)

moriszen, It sounds like the problem relates to the interface to the SD card rather than something to do with the Time Library. I would like to keep this thread focused on issues relating to the Time library.

Perhaps you can start another thread for a discussion on getting your SD card going.

Nice to see you got it posted .Does anyone know if the time library will work in idle - low power mode .I want to have an application that wakes up once or twice a day an logs the time and date (running on batteries) .any suggestions ?

The time library relies on the Arduino millis timer which services an interrupt every millisecond. This means it will not work in low power mode.

For an application that needs to wake up once or twice a day you would probably need to use a low power Real Time Clock that generated an interrupt that would wake up the Arduino when it needed to log something. Have a look in the playground to see if anyone has published an RTC application that does something like this.